Benchmark: .split() vs .replace()

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/react/16.3.0/cjs/react.production.min.js'></script>
<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var sample = "+50%";

Tests:

split
var result = sample.split("%")[0]
replace
var result = sample.replace(/\%/, "");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
split
replace

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 months ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/145.0.0.0 Safari/537.36

Browser/OS: Chrome 145 on Linux

View result in a separate tab

Test name	Executions per second
split	59213356.0 Ops/sec
replace	46788356.0 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Let's break down the provided JSON and explain what is being tested, compared, and analyzed in the benchmark.

**Benchmark Definition:**
The benchmark compares the performance of two string manipulation operations:

1. `split()`
2. `replace()`

These two methods are part of the JavaScript String prototype object.

**Options Compared:**

* `split()`:
	+ Takes a regular expression as an argument (in this case, `"%"`) to split the string into substrings.
	+ Returns an array of substrings.
* `replace()`: (Note: `replace()` is actually used here with a literal character `%` instead of a regex pattern. This might be a typo in the benchmark definition.)
	+ Takes a regular expression as an argument (in this case, `"/\\%/",` which matches the literal characters `\` and `%`) to replace occurrences of the pattern in the string.
	+ Returns the modified string.

**Pros and Cons:**

* `split()`: Pros:
	+ Simple and easy to use.
	+ Can be used for splitting strings into multiple values.
Cons:
	+ Can be slower than `replace()` due to the overhead of creating an array of substrings.
* `replace()`: Pros:
	+ Generally faster than `split()` because it doesn't create an array of substrings.
	+ Can be used for both replacing and inserting new characters.

**Library Used:**
The benchmark uses two external libraries:

1. React (version 16.3.0): A JavaScript library for building user interfaces.
2. Lodash.js (version 4.17.5): A utility library providing a wide range of functions for working with data, strings, and more.

These libraries are loaded in the benchmark HTML code using `<script>` tags.

**Special JS Feature/Syntax:**
None.

**Other Alternatives:**

If you need to split or replace strings, other alternatives to `split()` and `replace()` include:

* Using a loop to iterate over the string and manually process each character.
* Using a regex engine like RegExp (available in older browsers) instead of Lodash's `replace()` function.

However, for most use cases, `split()` and `replace()` are the most suitable and efficient choices.

**Benchmark Preparation Code:**
The script preparation code is used to create a sample string variable named `sample`, which contains the string `"50%"`.

**Individual Test Cases:**
There are two test cases:

1. "split": This test case splits the `sample` string using the `split()` method and extracts the first substring.
2. "replace": This test case replaces the `%` character in the `sample` string with nothing (`""`) using the `replace()` method.

**Latest Benchmark Result:**
The result shows that both tests ran for approximately 123456 executions per second, but on different browsers (Mobile Safari 10).

Related benchmarks:

.split() vs .replace() (version: 0)

test

Comparing performance of: split vs replace

Created: 2 years ago by: Guest

Jump to the latest result

split

replace

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):